1. A. Thrush, PT, DPT, Good Shepherd Penn Partners, 1800 Lombard St, Philadelphia, PA 19146 (USA).
2. M. Rozek, PT, DPT, Kittitas Valley Community Hospital, Ellensburg, Washington. At the time of the study, Dr Rozek's affiliation was with Good Shepherd Penn Partners.
3. J.L. Dekerlegand, PT, MPT, Good Shepherd Penn Partners.